Recording method

ABSTRACT

A recording material of a polymeric film comprising a polymeric film such as a polyester film and a layer of a bleachable dye such as a triphenylmethane type dye. The dye layer can be bleached with a writing instrument containing a bleaching agent to give a transparent clear drawing. The material is useful for overhead projection to give a clear image that is easy to see.

United States Patent Sugi et al.

[ RECORDING METHOD [75] Inventors: lchirow Sugi; Haruo Takenaka;

Toshiaki Okiyama, all of Tokyo; Teruo Kobayashi, Minami-ashigara, all ofJapan Fuji Photo Film Co., Ltd., Minami-ashigara, Japan Filed: Feb. 12,1974 Appl. No.2 441,784

Related US. Application Data Division of Ser. No. 214,215, Dec. 30,1971.

[73] Assignee:

[30] Foreign Application Priority Data Dec. 30, 1970 Japan 45-123039 US.Cl. 427/145; 8/4; 8/14; 8/69; 427/146; 427/150 Int. Cl. B44F l/lO; G03C11/22 Field of Search 8/4, 14, 69; 117/362, 117/368, 36.9, 1.7; 427/145,146, 150

[56] References Cited UNITED STATES PATENTS 1,642,774 9/1927 Grangell7/1.7

[ Dec.9,1975

2,922,690 l/l960 Mueller et a1. 8/21 3,148,934 9/1964 Brookens et a1...8/4

3,155,513 11/1964 Sorenson 96/91 3,367,797 2/1968 Sorenson 117/36.83,677,786 7/1972 Hollmann et a ll7/1.7

OTHER PUBLICATIONS Knechi et al., The Principles & Practice of TextilePrinting, pp. 663, 664, 1952.

Primary Examiner-Michael R. Lusignan Attorney, Agent, or FirmSughrue,Rothwell, Mion, Zinn & Macpeak [57] ABSTRACT 10 Claims, 5 DrawingFigures U.S Patent Dec. '9, 1975 FIG] l CYAN Iv 53m Iv mam RECORDINGMETHOD This is a division of application Ser. No. 214,215, filed Dec.30, 1971.

This invention relates to a recording material of a polymeric film, andmore specifically, to a polymeric film recording material comprising apolymeric film and a readily bleachable dye layer coated thereon.

A negative recording method wherein a non-transparent film layer iscoated on a polymeric film, and then the coated film layer is removedthereby to render it transparent and perform recording is one of thefeasible recording methods because of various merits such as the ease ofseeing, the freedom from eye fatigue, or the usability of a coatinglayer having various colors. The conventional methods, however, includea method wherein a film layer coated on the polymeric film is cut off byapplying a pressure to make it transparent, or by a method wherein thedesired parts of the coated film layer are stripped off to make themtransparent, both methods performing recording by applying-an externalphysical force. I

These recording materials, however, have the defect that letters,figures, etc., cannot be drawn freely thereon.

It has now been found that when a layer of a readily bleachable dye iscoated on a polymeric film and a recording is made by using a writinginstrument containing a bleaching agent, an oxidation reduction reaction(chemical reaction) occurs to bleach the dye layer, and recording isperformed easily, rapidly, and freely.

Accordingly, an object of the present invention is to provide arecording material on which letters, figures, etc., can be easily drawn.

Another object of the invention is to provide a negative material bycoating a dye layer readily removable by a remover on a polymeric filmand then bleaching the dye layer with a writing instrument containingthe remover utilizing an oxidation reduction reaction (chemicalreaction).

The invention will be described with reference to the accompanyingdrawings in which:

FIG. 1 is a sectional view of one example of the recording material ofthe invention;

FIG. 2 is a sectional view of one example of the recording material ofthe invention in which recording has been made with a writing instrumentcontaining a bleaching agent;

FIG. 3 is a sectional view of one example of the recording material oftheinvention in which recording has been made with a writing instrumentcontaining a bleaching agent and a dye;

FIG. 4 is a sectional view of another example of the recording materialof the invention; and

FIG. 5 is a sectional view of the recording material of the invention inwhich three colors are combined.

In these drawings, the reference numeral 1 designates a polymeric film,and a colored film layer which is readily bleachable with a bleachingagent is shown at 2, 2', or 2". The reference numeral 3 represents awriting instrument containing a bleaching agent. The bleached part ofthe film layer obtained by the writing instrument 3 is designated at 4.The reference numeral 5 shows a part on which recording has beenperformed in a color different from that of the coated layer uponbleaching the film layer with the writing instrument 3.

FIG. 5 shows that by combining three primary colors (yellow, magenta andcyan), various color phases can be selected.

The dyes that can be used in the dye layer of the invention must bereadily bleached by an oxidation reduction reaction. Examples of suchdyes that can be used in the invention are dyes expressed by thefollowing general formulae I, II and III. At least one of such dyes isdissolved in a solvent to be described, and the resultant solution iscoated on a polymeric film to form a dye layer. In order to improveadhesion between the polymeric film and the dye layer, a binder to bedescribed may be added to the solution of the dye layer.

General Formula I wherein R and R may be the same or different and eachrepresents a hydrogen atom, a lower alkyl group having 1 to 5 carbonatoms, an hydroxyalkyl group, a sulfoalkyl group, aryl group, or anaralkyl group; R and R are The dyes expressed by the general formula 1are triphenylmethane dyes. Since they are colored yellow, orange, red,violet, blue, and green, it is possible to choose various colors for useas a dye layer. Furthermore, since these dyes are soluble in a varietyof solvents such as alcohols or others to be described, the dye layerbecomes fast-drying. They are also readily bleached with a bleachingagent to be described, and

the color does not return to the original one. Examples of the dyes offormula 1 are listed below. The colors indicated are those obtained bycoloring.

I Examples of dyes Structure 1 H Color Yellow H C2 Reference Berichte37, 601 H 2A CH CH Color bluish green c 3 2 Reference Am. Chem., 206, 96

c CH CQOH 28 H C CH Color violet 3 3 H C CH3 N (c H 2 3 H -l- H Colorred f Reference c.1. 425:0 H H H N N 4 CH CH C 1 l t 3 3 cl kgf lenee4253s CH c -C H-N H3 5 C H C l bl I H\ 3 R f ence 42140 C H 5 Colorbluish green Reference CI. 42000 -continued I Examples of dyes Structure7 CH3 N 2 N CH3 so C 3 Color bluish green Reference Japanese PatentPublication No. 18637/65 8 OC H Color bluish violet CH H Reference C].43525 N C N CH 1 S0 Nc| H C N CH 9 H H Color blue MM Reference Disulfonecompound of Cl. 42755 SO so NH 3 C N "a H H 10 C H Col bl 2 5 2 5 Refzl'ence 42655 g I I l I o No w 3 V so V H-N-CO H 11 C H C H c 1 bl 4 4 9Rzf l ence 42655 l NuO 'S-CH Cl' -'C--NCH C H -SO H-N--OC2H 12 C H 3 C HColor blue Reference C]. 42705 C HOCH CH CH H OH N- C '1 N Cl HOC H C HCH C l'l oH -continued I Examples of dyes Structure 13 COONO Color redviolet Reference CI. 43565 C H 2 5 c C H 3 COON 1 C1 CQOH Color redviolet R fere CI. 43570 C2 H5 e nce N C OH c H 2 5 CH COOH 15 C H I C HColor green 3 N- C--N 3 c1- Reference CI. 42010 c C H H 3 C H COOH 3 16H Color green Reference Journal of Chemical Society, 41, 193 andBerichte 15, 23.7

General formula II where R is H, lower alkyl having 1 to 5 carbon atoms,aryl group, or COOM, M being hydrogen atom, alkali Structure Color IIExamples of dye H'C C Yellow -continued [1 Examples of dye StructureColor l 8 C H3 C C CH Q Light yellow N c=o c1 19 c H -c C=CH- OCH Yellow21 Yellow M II I Cl C1 CH 22 KOOC-C C =CH N 3 Orange red u N C 0 23 C HCOC-C C C Yellow -continued ll Examples of dye Structure Color C H 24 CHC C =C N 2 5 Yellow orange II I N C=O SO NH General formula III whereinR is lower alkyl group having 1 to 5 carbon CH CH atoms, R is loweralkyl, substituted alkyl group, or aryl 3 group; R is hydrogen atom ormethyl; R is hydrogen c 25 atom, halogen group and carboxymethyl group;and X 11 8 is an anion.

The general formula III represents indolinostyryl type N R 9 dyes whichare red to violet, soluble in solvents such as 1c alcohols and readilybleached with bleaching agents to CH 30 be described, the colors notreturning to the originals.

3 Examples of dyes of formula III include:

lll Examples of dyes Structure CH CH3 Color pink 25 Reference CI. 48015C CH I or 3 N CH CH C1 CH cl CH c 1 k 26 g; 3 Rgfgr ence 48013 C CH 3C-CHCH N N CH CH CH 2 2 CH 3 c1 27 CH CH v Color red violet 3 3Reference c1. 48020 C c 2 I C-CH' CH- N N CH ol-l c! CH cl 28 CH3 CH3Color red Reference CI. 48013 c -CH=C N C2H5 1 N 2 5 CH c1 -continuedIll Examples of dyes Structure 29 CH CH Color violet 3 CH3 ReferenceC.I. 8030 r I 4 CH COC C I CCH:CH-- N- 06 N v 4 2v 5 N CH C 30 C H CHColor violet 3 CH3 Reference C.I. J 48025 C C W3: c-c|-|=c|-|- N--OC H CCH 3 1 General formula 7 wherein R and R are hydrogen atom, alkyl groupof not more than 5 carbon atoms and may be the same or R 0 35 differentand X is an acid residue.

i111 R} x R2 C N \R Examples of dyes R1 R2 Color m 22 2.. a 2: 40 37 cu:ca;, 111:: 38 C 11 H blue group; and X is an acid residue.

General formula V Examples of the solvent used for dissolving the dyesI, II, III, IV, and V above include lower alcohols such as methanol,ethanol or propanol, or other readily evaporating and drying organicsolvents such as acetone, or dioxane. Mixtures of water with the organicsolvents can also be used.

include tragacanth rubber, British rubber, sodium alginate, polyvinylalcohol, and carboxymethyl cellulose which are used mainly as aqueoussolutions, and synter, or cellulose acetate maleic acid ester which areused mainly as alcohol, acetone, or dioxane solutions. The amount of thebinder used in the invention is adequately 50 to 500% based on theweight of the dye. The use of more than 500% causes difficulty ofbleaching.

The solution containing these dyes or binders is coated on a film of apolymer such as polyethylene terephthalate, cellulose esters,polycarbonate, vinyl polymers or polystyrene, to thereby form a dyelayer.

As the bleaching agent for the dye layer, addition 0 u/s \C l C V MNproducts of sulfites and/or bisulfites with formaldehyde are used (thesalts here are sodium, potassium and ammonium salts). Examples of otheruseful bleaching agents include sodium bisulfite, hydrosulfite, anaddition product of hydrosulfite with formaldehyde, sodium sulfoxylateformaldehyde (NaHSO .CH O.2l-l O) sulfur dioxide gas, sodium sulfide,thiourea dioxide, hydrazines such as hydrazine hydrate, or phenylhydrazine, and amines such as ethanolamine or butylamine.

A solution of the bleaching agent in water or an organic solvent such asalcohols, e.g. methanol or ethanol, and ketones such as acetone ormethyl ethyl ketone is put in a writing instrument such as sign pens ormagic pens.

If desired, a dye which is difficult to bleach with said bleaching agentmay be incorporated in the bleaching agent. By this, it is possible toform a color of the dye incorporated in the writing instrument on thebleached part of the coated dye layer. Examples of dyes which 20 aredifficult to bleach are:

SO Na Color yellow mi 7/ so Na l so Na Color red Color I0 NH Cll S0 lNa.

O OH violet; (3.1. 60730 Color blue;

The recording material so obtained finds a variety of applications suchas overhead projection or drafting. When it is used as a film foroverhead projection, it is easy to see without causing eye fatigue.Moreover, various colors can be chosen for use in background, that is, acoated film layer. Using this material, recording can be performedfreely and rapidly, and a negative can be obtained with simplicity.

The invention will be described specifically by the following Examples.

EXAMPLE 1 Dye No. 2A (3 g) was dissolved in 100 g of methanol to preparea dye solution (solution A). On the other hand, 5 g of a copolymer ofvinyl acetate and maleic anhydride was dissolved in 100 g of ethylalcohol to prepare a binder solution (solution B). These solutions A andB were mixed with each other, and the mixed solution was coated on a100p. thick film of cellulose triacetate, and dried to form a blue film.

Separately, 5 g of ammonium sulfite was dissolved in 50 g of water and50 g of methanol to form a bleaching agent solution in a sign penreceptacle. Writing was made on the blue film using this sign pen. Acolorless transparent line drawing was obtained. When it was projectedwith an overhead projector, a clear image was obtained which did notgive fatigue to the eyes.

EXAMPLE 2 Dye No. 2B (5 g) was dissolved in 50 g of methanol and 50 g ofmethylene dichloride. To the resultant solution was added a bleachingagent solution of g of a polycondensate of salicylic acid withformaldehyde in 100 g of ethanol. The mixed solution was coated on a 75n thick polyester film, and dried to form a violet film. Writing wasmade on the film obtained, using a 5% aqueous solution of sodium sulfite(or 10% ethanolamine methanol solution or 10% hydrazine hydrate methanolsolution). A colorless transparent line drawing was rapidly obtained.

EXAMPLE 3 Example 2 was repeated except that dye (a) (yellow dye whichis difficult to bleach; dye table No. 49000) was put into the bleachingagent solution in an amount of 1% by weight. A yellow line drawing wasobtained in the resulting violet film.

EXAMPLE 4 Example 1 was repeated except using each of dyes Nos. 1 and 3to 34, to obtain films of the colors indicated hereinabove. When writingwas made on each of the film using the bleaching agent solution, acolorless transparent line drawing was obtained, and the film permittedthe projection of an image that could be easily seen.

EXAMPLE 5 Dye No. 35 (2 g) was dissolved in 100g of chloroform. On theother hand, 5 g of a copolymer of vinyl butyl ether and styrenesulfonicacid was dissolved in 100 g of ethanol. The resultant solutions weremixed with each other. Subsequently, the sameprocedure as set forth inExample 2 was repeated to form a blue film. A colorless and transparentline drawing was rapidly obtained using a bleaching agent solution.

The same results were obtained with dyes Nos. 36 to 38.

EXAMPLE 6 A 1% aqueous solution of dye No. 6 (2.5 g) was mixed with 2 gof a 10% aqueous solution of gelatin, and the mixed solution was coatedon a transparent p. thick polyester film to form a cyan colored layer.When writing was made on the film using a 20% methanol solution ofethanolamine, a colorless transparent line drawing was obtained rapidly.

On the other hand, 4 g of a 1% aqueous solution of dye No. 20 and 3 g ofa 10% aqueous solution of gelatin were similarly coated on anotherpolyester film to form a yellow layer. On the back of this film werecoated 1.5 g of a 1% aqueous solution of dye No. 26 and 2 g of a 10%aqueous solution of gelatin to form a magenta la er.

Writing was made with a 10% aqueous solution of sodium sulfite onsuitable places of these front and back surfaces. The written parts werebleached. FIG. 5 shows the superposition of these two films.

What is claimed is:

l. A recording method which comprises drawing on a coated film with awriting instrument having a bleaching agent, said film being transparentand having at least-one layer of a dye bleachable by said bleachingagent coated thereon, said bleaching agent bleaching said dye to causeit to become transparent.

2. The recordingmethod of claim 1, wherein said bleaching agent in saidwriting instrument includes a dye which is resistant to bleachingwhereby the areas of said layer of dye bleached by said bleaching agentare colored by the bleach-resistant dye. I

3. A method of recording on a transparent polymeric film for overheadprojection comprising drawing on a layer of a bleachable dye coated onthe transparent polymeric films with a writing instrument which has ableaching agent therein, said bleaching agent of said writing instrumentbleaching said bleachable dye such that the recording is obtained.

4. The recording method of claim 3, wherein said layer of said dyecontains a binder which improves the adhesion between said transparentpolymeric film and said layer of said bleachable dye.

5. The recording method of claim 3, wherein a dye which is resistant tobleaching with said bleaching agent is incorporated in said bleachingagent in said writing instrument, said dye thereby coloring the areasbleached by said bleaching agent.

6. The recording method of claim 3, wherein said bleachable dye isbleachable by an oxidation-reduction reaction of said dye and saidbleaching agent.

7. The recording method of claim 3, wherein said bleachable dye is amember selected from the group of dyes listed below as represented byFormulae I, II, III, IV and V:

wherein R and R may be the same or different and each represents ahydrogen atom, a lower alkyl group having 1 to 5 carbon atoms, ahydroxyalkyl group, a sulfoalkyl group, an aryl group or an aralkylgroup; R and R are I wherein R, and R are the same as R, and R ahydrogen atom, a hydroxyl group, a halogen atom, a lower alkyl grouphaving 1 to 5 carbon atoms, an alkoxy group, a carboxyl group, or asulfone group and may be the same or different; phenylene nucleus 1 maybe sub- 50 stituted by an alkoxy group, a halogen atom, or a lower alkylgroup having 1 to 5 carbon atoms, n is from 1 to 3; and X is an anion oran anion of an intramolecular salt;

CHK /CH3 wherein R is a hydrogen atom, a lower alkyl group having 1 to 5carbon atoms, an aryl group, or COOM wherein M is a hydrogen atom, analkali metal, ammonium, or a lower alkyl group having 1 to 5 carbonatoms, R is a hydrogen atom, a hydroxyl group, $0 M wherein M is ahydrogen atom, an alkali metal, or ammonium, an alkoxy group, a halogenatom, or a dialkylamino group; and R is a hydrogen atom, a lower alkylgroup having 1 to 5 carbon atoms, or an aryl group;

H=CH wherein R is a lower alkyl group having 1 to 5 carbon atoms; R is alower alkyl group having 1 to 5 carbon atoms, a substituted alkyl group,or an aryl group; R is a hydrogen atom or a methyl group; R is ahydrogen atom, a halogen atom, or a carboxymethyl group; and X is ananion;

coon

wherein R and R are lower alkyl group or not more than 5 carbon atoms; Rand R are hydrogen atom, lower alkyl group having 1 to 5 carbon atoms,or am]- kyl group; and X is an acid residue;

wherein R and R may be the same or different and each represents analkyl group of not more than 5 carbon atoms, and X is an acid residue.

8. The recording method of claim 3, wherein said bleaching agent isselected from the group consisting of addition products of sulfites,bisulfites, or both sulfites and bisulfites with formaldehyde, sodiumbisulfite, hydrosulfite, an addition product of hydrosulfite withformaldehyde, sodium sulfoxylate formaldehyde, sulfur dioxide gas,sodium sulfide, thiourea dioxide, hydroazines, and amines.

9. The recording method of claim 4, wherein said binder is a memberselected from the group consisting of tragacanth rubber, British rubber,sodium alginate, polyvinyl alcohol, carboxymethyl cellulose,polycondensates of a member selected from the group consisting ofcresol, salicylic acid and oxyphenylacetic acid weight based on theamount of said dye.

1. A RECORDING METHOD 3HICH COMPRISES DRAWING ON A COATED FILM WITH AWRITING INSTRUMENT HAVING A BLEACHING AGENT, SAID FILM BEING TRANSPARENTAND HAVING AT LEAST ONE LAYER, OF A DYE BLEACHABLE BY SAID BLEACHINGAGENT COATED THEREON, SAID BLECAHING AGENT BLEACHING SAID DYE TO CAUSEIT TO BECOME TRANSPARENT.
 2. The recording method of claim 1, whereinsaid bleaching agent In said writing instrument includes a dye which isresistant to bleaching whereby the areas of said layer of dye bleachedby said bleaching agent are colored by the bleach-resistant dye.
 3. Amethod of recording on a transparent polymeric film for overheadprojection comprising drawing on a layer of a bleachable dye coated onthe transparent polymeric films with a writing instrument which has ableaching agent therein, said bleaching agent of said writing instrumentbleaching said bleachable dye such that the recording is obtained. 4.The recording method of claim 3, wherein said layer of said dye containsa binder which improves the adhesion between said transparent polymericfilm and said layer of said bleachable dye.
 5. The recording method ofclaim 3, wherein a dye which is resistant to bleaching with saidbleaching agent is incorporated in said bleaching agent in said writinginstrument, said dye thereby coloring the areas bleached by saidbleaching agent.
 6. The recording method of claim 3, wherein saidbleachable dye is bleachable by an oxidation-reduction reaction of saiddye and said bleaching agent.
 7. The recording method of claim 3,wherein said bleachable dye is a member selected from the group of dyeslisted below as represented by Formulae I, II, III, IV and V:
 8. Therecording method of claim 3, wherein said bleaching agent is selectedfrom the group consisting of addition products of sulfites, bisulfites,or both sulfites and bisulfites with formaldehyde, sodium bisulfite,hydrosulfite, an addition product of hydrosulfite with formaldehyde,sodium sulfoxylate formaldehyde, sulfur dioxide gas, sodium sulfide,thiourea dioxide, hydroazines, and amines.
 9. The recording method ofclaim 4, wherein said binder is a member selected from the groupconsisting of tragacanth rubber, British rubber, sodium alginate,polyvinyl alcohol, carboxymethyl cellulose, polycondensates of a memberselected from the group consisting of cresol, salicylic acid andoxyphenylacetic acid with formaldehyde, acrylic acid polymers,methacrylic acid polymers, styrene carboxylic acid polymers, a copolymerof vinyl chloride and acrylic acid, a copolymer of vinyl chloride andmaleic anhydride, a copolymer of acrylonitrile and styrene carboxylicacid, a copolymer of vinyl acetate and maleic anhydride, a copolymer ofstyrene and maleic anhydride, a copolymer of vinyl butyl ether andstyrene sulfonic acid, cellulose acetate phthalic acid ester, andcellulose acetate maleic acid ester.
 10. The recording method of claim4, wherein the amount of said binder ranges from 50 to 500 percent byweight based on the amount of said dye.